We have seen hackers flooding 911 emergency service with rogue requests to knock the service offline for an entire state, but some hacking incidents are worse than others.

One such incident took place in Dallas on Friday night when hacker triggered a network of 156 emergency warning sirens for about two hours, waking up residents and sparking fears of a disaster.

The emergency warning sirens — designed to warn citizens of the Texas about dangerous weather conditions, such as severe storms and tornados — were activated around 11:40 p.m. Friday and lasted until 1:20 a.m. Saturday.